Question

For any two vectors a and b, if $\mathbf{a} \times \mathbf{b} = \mathbf{0},$ then

• A. $\mathbf{a} = \mathbf{0}$
• B. $\mathbf{b} = \mathbf{0}$
• C. Not parallel
• D. None of these

Answer 1

Answer: (D)

None of these

Answer 2

$\mathbf{a} \times \mathbf{b} = \mathbf{0},$ even if $\mathbf{a} \neq \mathbf{0},\mathbf{b} \neq \mathbf{0}$ i.e., $\mathbf{a}$ and $\mathbf{b}$ are parallel.